Rotary engine.



F. A. SHOEMAKER.

ROTARY ENGINE.

APPLICATION FILED MAY 14, 1915.

1,281,677., Patented Oct. 15, 1918..

5 SHEETSSHEET I.

F. A. 'SHOEMAK'ER.

ROTARY ENGINE.

APPLlCATlON FILED MAY I4. 1915.

Patented Oct. 15, 1918.

SSHEETS-SHEET 2 r. A. SHOEMAKER.

ROTARY ENGINE. REPUCATION FILED MAY 14.1915

138L677. Y Patented Oct. 15, 1918.

5 sussrs-su:n a.

F. A. SHOEMAKER.

ROTARY ENGINE.

APPUCATION FILED MAY $4. 1915.

1,281,677". Patented Oct. 15, 1918.

5 SHEETS-SHEET 4- Emma/mm F. A. SHOEMAKER.

ROTARY ENGINE. v APPLICATION FILED MAY14.19|5.

1,281,677. Patented 0ct.15, 1918.

5 SHEETSSHEET 5.

flan/Z127: JZoemaZZ r. 12/6 2237 FRANK A. SHOEMAKER, OF BUFFALO, NEW YORK, ASSIGNOR T0 BROWN ROTARY ENGINE 00., OF NIAGARA FALLS, NEW YORK, A CORPORATION OF YORK.

ROTARY ENGINE.

Specification of Letters Patent.

Patented Oct. 15, 1918.

To all whom it may concern:

Be it known that 1, FRANK A. SHOE- MAKER, a citizen of the United States, resid* ing at Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Rotary Engines, of which the following is a specification.

My invention relates to improvements in rotary engines, it may also be said to relate incidentally to pumps of the type employing a rotary pumping medium inclosed within a casing.

The primary object of my invention is to provide a rotary engine having self-balanced inlet valves of improved construction to the end that they may operate with greater free dom and ethciency and to provide said valves with a plurality of inlet ports and synchronously time the same to the movement of the blades or pistons of the rotor.

A further object is to provide a rotary engine of generally improved construction with a view of simplifying the same, providing for the balancing of parts so as to avoid jar or pounding, and to otherwise improve on rotary engines now in use.

The invention consists in the novel features of construction and in the combination and arrangement of parts to be hereinafter described and particularly pointed out in the subjoined claims.

In the drawings,

Figure 1 is a side elevation of an engine embodying my invention.

Fig. 2 is an end view of the same viewed from the left of Fig. 1.

Fig. 3 is an enlarged longitudinal section taken on line aa, Fig. 2.

Fig. 1 is a transverse section taken on line Z)b, Fig. 3,

Fig. 5 is a fragmentary transverse section taken on line 0-0, Fig. 3.

Fig. 6 is a fragmentary transverse section taken on line dd, Fig. 3.

Fig. 7 is a transverse section taken on line ce, Fig. 3.

Fig. 8 is a longitudinal section through a portion of the engine taken on line f-f, Fig. 1.

Fig. 9 is a longitudinal section through one of the inlet or admission valves taken on line g-5], Fig. 4.

a portion of the engine-taken on line hh, Fig. 1.

Fig. 11 is a detached perspective view of one of the armed collars secured to the shafts of the admission valves.

Fig. 12 is a longitudinal section taken on line 11-71, Fig. 6.

Fig. 13 is a detached perspective view of i one of the upstanding blade-actuating members.

Reference being now had to the drawings in detail, like numerals refer to like parts in the several figures.

15 designates the casing or cylinder of the engine which, in the main, is exteriorly of cylindrical formation and has a cylindrical bore or interior in which the rotor 16 is concentrically arranged. This casing or cylinder is cast with its opposite ends open and these ends are closed by heads 17 bolted to flanges 18 at opposite ends of the cylinder, or which may be otherwise fastened to said cylinder. The casing or cylinder is provided with longitudinally-disposed integral tubular extensions 19, 20, 21 and 22, the extensions 19 and 20 serving as exhaust chambers which are in communication with the interior of the casing by means of exhaust ports 23, 24, respectively, while the tubular extensions 21, 22 serve as steam admission chests which are in communication with the interior of the casing by means of inlet ports 25, 26, respectively.

As clearly shown, an exhaust chamber is arranged in close proximity to each steam admission chest, and while so arranged they are not thus paired, since the exhaust chamber at one side of the cylinder or casing is paired or cooperates with the steam admis sion chest at the opposite side of the cylinder. There are consequently two pairs of tubular extensions which may be integrally cast with the cylinder or. attached thereto in any steam-tight manner.

The rotor is secured to a rotor shaft 27 extending through stufling boxes or packings 28 applied to the head 17 of the cylinder or casing, and this shaft is journaled in roller bearings 29 inclosed within castings 3O secured to said heads. A fly wheel 31 is attached to said shaft and each of the castings 30 is equipped with oil cups 32 by means of which the roller bearings are lubricated. The rotor is in the form of a holiow cyiinder, somewhat shorter than the interior of the cylinder or casing, with integral webs 33 extending inwardly from the cylindrical wall, said web being spaced equi-distantly within the cylinder and having-gu'ide-ways Arranged for movethe casing by an annular space .37, which space is divided by the abutments or walls 36 into two semi-annular chambers 38, 39, each chamber having an inlet port opening thereinto' at one end and an exhaust port opening thereinto at its other end; for example, the inlet port 25 opens into the upper semi-annular steam chamber 38 near the left hand end of the same as shown in Fig. 4, while the exhaust port 23 opens into said steam chamber near the right hand end thereof, and as these ports are connected, respectively, with the steam admission chest 21 and exhaust chamber 19 said chest and chamber are paired while the steam adinission chest 22 is paired with the exhaust chamber 20, and in like manner cooperate with the lower semi-annular steam cham ber 39.

As clearly shown in Fig. 4, the inlet ports are arranged diametrically opposite each other while the exhaust ports are likewise arranged and the inlet ports are entirely separated from each other as are the outlet ports by the abutments or partition walls 36. By arranging the inlet and exhaust ports in the manner described, the steam enters the cylinder or casing at diametrically opposite points and acts upon the blades or pistons of the rotor at opposite points of the rotor so that the pressure against the latted is equalized and balanced action ob tained.

As herein stated, the rotor is somewhat shorter than the cylinder and for-this reason I have provided at opposite ends of the rotor suitable packing means; suitable take up means, and suitable piston or blade actuating means; said means occupying the space between the heats of the cylinder and the ends of the rotor. In order to operate in conjunction with the take-up means and actuating means I provide each of the pistons or blades at opposite ends thereof with extensions or arms 40, said extensions or arms being inclined toward the axis of the rotor and extending through radial guide same and the rotor and also for the reason that they are provided with peripheral packing members acting against the ends of the rotor at the peripheral marginal portion and against the inner surface of the casing. For this purpose the disk is rabbeted, as at 45, around its peripheral edge, and in the rabbet thus formed is arranged an L-shaped packing annulus 46 having its horizontal web lying against the rabbetcd portion of the disk, as at 47, and its outstanding web in contact with the end of the rotor at its marginal portion, as at 4:8. This provides spaces between the side walls of the rabbets of said disks and the outstanding Webs of the L- shaped packing annuli, and in each of these spaces split rings 4-9, 50 are arranged, said rings being self-expanding so that the outer ring travels in contact with the inner surface of the casing.

Each of the heads 17 is internally recessed, as at 51, and in each of these recesses a cam 52 is secured, the cams being secured by means of bolts 53 which also secure the castings 30 to the exteriorof the heads. These cams may be termed idle cams, since they are fixed and are adapted to have the parts co-actin therewith travel around the same and at least at times in contact with the perimeter thereof. The recesses in which these cams are secured are somewhat larger than the cams and have their peripheral walls made to conform to the edges of the cams so that cam grooves 54 are provided havin opposite indented portions 546. In a broad sense these cams may be considered as forming parts of the heads and when so considered it may be stated that the heads are provided with the cam grooves 5 since if these (grooves were machined into the head the same results would be obtained.

Between the heads or the heads and cams and the packing disks 42, take-up disks 55 are interposed, these disks being. rotatable with the packing disks and rotor and each is provided with radial guide grooves 56 on their inner surfaces in which are arranged for radially reciprocating movement combined take-up and actuator members 57, each member having an inwardly opening pocket 58 to receive the adjacent extension or arm 4-0 of the cooperating piston or blade. Each of these members 57 is provided with a longitudinal bore 59 extending inwardly from the pocket 58 and having an expanding coiled spring 60 inserted therein which bears against the end edge of the extension or arm 40. A set screw 61 is threaded into the inner end of said bore against which one end of the coiled spring bears and by means of which the tension on the spring may be regulated so as to force the coacting piston or blade outwardly to maintain the longitudinal outer edge of the latter in contact under proper pressure with the inner surface of the casing. Each of these reciprocating members is also provided with a longitudinal bore 62 extending outwardly from the pocket 58, and in this longitudinal boreadjustable stop pins 63 are situated, said stop pins being enlarged at their outer ends and threaded to screw into the enlarged outer ends of the bores. The stop pins are therefore adjustable and in this manner the extent to which the pistons or blades may be moved outwardly by the springs is controlled absolutely. As soon as wear is perceptible on the outer longitudinal edges of the pistons or blades these stop pins may be adjusted, whereupon the coiled springs 60 will immediately act to take up the wear. This construction assures highly eflicient action of the engine at all times.

Extending through the take-up disks are radially-disposed guide slots 65 through which extend studs formed on the actuator members 57, said studs entering the cam grooves 54 and having rollers rotatably mounted thereon which travel in said grooves in contact with the peripheral edges of the cams 52. These rollers are a trifle smaller in diameter than the width of the cam grooves so that they act freely and without resistance against the walls of said grooves. I

The rotor 16 is provided with a plurality of circumferentially arranged webs 66 which form peripheral grooves 67, and the abutments or partition walls 36 are notched, as at 68, to receive the peripheral webs of the rotor, the notching of said abutments or walls providing entering portions 69 which snugly fit within the peripheral grooves of the rotor and tend to minimize the chances of leakage of steam between these abutments and the rotor.

In Figs. 3 and 8 it will be seen that two of these webs are formed at extreme opposlte ends of the rotor and that the L-shaped packing annuli as bear against the outer faces of these end webs, thus preventing the escape of steam between the packing disks and the ends of the rotor; while the packing rings 49, 50, prevent escape of steam along the inner surface of the casing.

Within each of the steam admission chests, which are preferably cylindrical in cross section, is a hollow rotating valve 7 0 which is in the form of an elongated cylindrical tube snugly fitting within the chest and haying a plurality of elongated steam ports 41 formed therein, said ports being coextensive with the pistons and being adapted to be brought successively into registration with the inlet ports 25, 26, but only momentarily so. In fact, more particularly describing the action of the valves, these ports are made to pass successivel over the inlet ports. Each of these valves as a plurality of pairs of internal lugs 72, and between these pairs of lugs are fitted studs 73 extending laterally from the arms of a compensating spider 74 fastened to a valve shaft 75. The valve shafts of both valves extend through the steam admiss1on chests and through entrance chambers 7 6 cast integral or secured in any practicable manner to a U-shaped steam inlet pipe 7 7 having a main feed inlet 78 so that the steam entering through said feed inlet branches oif through opposite ends of the U-shaped steam pipe and enters both steam admission chests where it is controlled by the valves within said chests. These steam entrance chambers 7 6 are provided with packing boxes 86 through which the valve shafts 75 extend, and at their outer ends these shafts areprovided with sprocket wheels 87 around whlch pass sprocket chains 7 9 which are operated by 'a double sprocket wheel 80 on the rotor shaft 27 around which said chains also pass and by which they are driven.

Each of the sprocket wheels 87 is provided with a hub portion 81 and a rim portion 82, said hub portion having segmental slots 83 through which are passed set screws 84 that take into the overlapping part 85 of the rim portion 82. This construction of sprocket wheel permits each of the steam inlet valves to be adjusted rotatably independently of the other so that the ports of said valve may be positioned to pass over the inlet ports 25, 26, at the proper moments.

The connection of the compensating spider to the valve in the manner described is a very desirable feature of my invention owing to the length of the inlet valves to which i they are connected, as the necessary play is provided between the shaft and valve to permit the latter to rotate freely without binding and to compensate for any deviation from true alinement or parallelism, relatively. This is particularly true when the bearings of the valve shafts become worn, or when the heat of the steam causes slight warping of parts.

The operation of the engine is as follows,-

In starting the engine it is of course necessary that the parts be rotated to bring one of the steam ports 71 of the valves into registration with the inlet ports 25, 26, if not already so disposed, whereupon the steam enters the upper and lower semi-annular steam chambers of the cylinder at diametrically opposite points. The action of the steam against the pistons 35 causes the rotation of the rotor, and as the inlet valves act in unison with the rotor the rotary movement of the latter causes the valves to rotate and cut off the supply of steam to the cylinder. The steam is therefore used expansively until the pistons or blades against which it acts are brought to the exhaust ports 23. However, before the pistons or blades against which the steam is acting ex pansively are moved to the exhaust ports, the succeeding pistons or blades are ad vanced and moved over the inlet ports, when the next steam ports in the valves are moved over said inlet ports and permit the live steam to enter the cylinder and act upon said lastmentioned pistons or blades. In this manner steam is acting underpressure against one blade in each steam chamber and expansively against another and as similar action of the steam takes place at diametrically opposite points of the rotor the engine may be said to be perfectly balanced.

The springs 60 in the piston-actuating members 57 tend to hold the blades against the inner peripheral surface of the casing, except when they are drawn inwardly by the outer walls of the cam grooves, and this action takes place as they approach the abutments or partition walls 36, as will be clear upon examination of Figs. 4c and 7. Immediately that the pistons pass said abutments or partition walls, they are moved outwardly by the inner Walls of the cam grooves and again brought into contact with the in ner peripheral surface of the casing. Attention is drawn to the fact that the steam used expansively within the steam chambers of the cylinder acts against the fixed abutments 36 until the piston passing over said abutment is fully extended and comes into contact with the peripheral wall of the casing, at which moment the steam valves have brought steam ports into registration with the inlet ports 25, 26 to admit live steam. In this manner all tendency of the steam being used expansively to act in reverse manner against any of the piston blades, except to a slight degree, is fully overcome by the live steam behind the succeeding pistons or blades.

Having thus described my invention, what I claim is,

1. A rotary engine comprising a casing, a rotor arranged concentrically Within said casing and spaced from the surrounding wall of the casing by a steam chamber, said rotor having guide-ways formed therein, pistons in said guide-ways having integral narrowed end extensions, piston actuating members at opposite ends of said rotor and rotatable therewith; adjustable stops in said piston actuating members independent of said end extensions against which the outer edges of said end extensions bear, and springs carried by said piston actuating members and acting against the inner edges eaner/7 of said end extensions to retain the latter against said stops.

2. A rotary engine comprising a casing having a. cylindrical wall and heads at opposite ends thereof, a rotor spaced from said cylindrical wall, abutments extending from said cylindrical wall to said rotor to divide the space between the two into two semi-annular steam chambers, said rotor having guide-ways, pistons arranged within said guide-ways and each having integral end extensions, a cam on one of said heads, and combined take-up and actuator members interposed between said cam and said end extensions.

3. A rotary engine comprising a casing, a rotor within said casing having piston guide-ways, pistons reciprocable within said guide-ways having narrowed end extensions, piston actuating members at opposite ends of said rotor and rotatable therewith; adjust-able means carried by said piston actuating members acting against the outer edges of said end extensions and retained independent of the latter to control the exact outward movement of said pistons, springs carried by said piston actuating members and acting against the inner edges of said end extensions to force the latter against said adjustable controlling means, and means for adjusting the tension of said springs.

A rotary engine'comprising a casing having a cylindrical wall, a rotor within said casing provided with piston guideways, pistons reciprocabl'e within said guideways, a disk secured to each end of said rotor and each having a rabbet formed in its peripheral edge, L-shaped packing annuli fitting into the rabbets of said disks and bearing against opposite ends of the rotor at their marginal portions, and packing rings fitting into the L-shaped packing annuli and adapted to bear against the cylindrical wall of the casing.

5. A rotary engine comprising a casing having a cylindrical Wall and heads at op posite ends, each head having a cam groove on its inner face, a rotor within said casing having piston guide-ways, pistons within said guide-ways having narrowed end extensions at opposite ends, a disk at opposite ends of the casing rotatable with said rotor and having radial guide grooves therein and guide slots extending therethrough from said guide grooves, combined take-up and actuator members within said guide grooves receiving the extremities of the end exten-- sions of said pistons and having studs extending through said guide slots adapted for cooperation with said cam grooves.

6. A rotary engine comprising a casing having a cylindrical wall and heads at opposite ends with depressions in their inner faces, cams secured in said depressions and having their peripheral edges spaced from the side walls of said depressions to provide cam grooves, a rotor within said casing having piston guide-ways, pistons within said guide-ways having end extensions, disks, rotatable with said rotor and lying at opposite ends thereof, said disks having openings through which the end extensions of said pistons project, disks between said firstmentioned disks and the heads of said casing provided with guide grooves and with guide slots extending outwardly from said grooves, reciprocating members within said guide grooves having outwardly projecting studs extending through said guide slots and rollers on said studs acting within said cam grooves, said reciprocating members having the extending ends of the pistons entered thereinto, adjustable stop pins within said reciprocating members against which said end extensions bear, and springs within said reciprocating members bearing against said and extensions to retain the same against said stop pins.

7. In a rotary engine, a cylindrical steam admission chest, a rotary valve within said chest and co-extensive therewith, said valve having an elongated port and having also internal lugs arranged in pairs at points between its ends, a valve shaft passing through said valve, and a spider secured to said valve shaft and having portions extending between the pairs of lugs in said valve.

8. In a rotary engine, a steam admission chest having an elongated cylindrical bore,

a rotatable valve coextensive with said bore and having a plurality of elongated inlet ports, said valve having a plurality of pairs of internal lugs at a point between its ends, a shaft co-axial with said 'valve, and a spider secured to said shaft and having laterally extending studs each stud being positioned between a pair of said lugs.

. 9. In a rotary engine, a steam admission chest having an elongated cylindrical bore, a hollow rotary valve within said bore provided with a plurality of elongated steam ports and with a plurality of pairs of internal lugs arranged in circular series midway between the ends of the valve, a shaft co-axial with said hollow valve, and a spider secured to said shaft and having radial arms with laterally extending studs adapted to enter between said pairs of lugs.

10. A rotary engine comprising a casing having a pair of steam inlets and a pair of steam exhausts, a rotor within said casing, pistons reciprocably arranged on said rotor, a pair of steam admission chests into which said steam inlets open, a rotary valve in each of said steam admission chests, means for rotating said valves, and means for separately adjusting said valves within said steam admission chests, said adjusting means being operable independent of the means for rotating said valves.

In testimony whereof I afiix my signature.

FRANK A. SHOEMAKER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). G. 

